FIG. 1 is a perspective view showing an installation process of a typical submersible pump. An elbow pipe 2 is fixed to the bottom of a water tank (not shown), a strut 1 is fixed at the top of the water tank, top ends of a pair of guide bars 3 are fixed to a bracket 9 to which the strut 1 is attached, the bottoms of the guide bars 3 are fixed to the elbow pipe 2, and a coupling member 5 is coupled to one side of a submersible pump 4. In this state, if it is sought to install the submersible pump 4 in the water, if a hoist (not shown) is actuated to hang down a pulling rope 6, the submersible pump 4 falls while being guided to the guide bar 3 by means of its self weight. Thus, a flange 7a formed in a discharge port 7 of the submersible pump 4 is coupled to a flange 2a formed on the inlet side of the elbow pipe 2, so that the discharge port 7 of the submersible pump 4 communicates with the elbow pipe 2.
Accordingly, if electric power is supplied to the submersible pump 4 through a power line 8, the submersible pump 4 is driven, so that water within the water tank is discharged to the outside through the discharge port 7 of the submersible pump 4, the elbow pipe 2, and an exhaust pipe (not shown) coupled to a flange 2b on the outlet side of the elbow pipe 2. When the submersible pump 4 is driven, a high pressure occurs within the discharge pipe 7 of the submersible pump and the elbow pipe 2. Due to this, mutually pushing force occurs in the discharge pipe 7 and the elbow pipe 2 and therefore a gap is intermittently formed between the discharge pipe 7 of the submersible pump and the elbow pipe 2. Accordingly, a problem arises because the water discharged from the submersible pump 4 is leaked between the discharge pipe 7 and the elbow pipe 2.
The inventor of the present invention made an invention for preventing a phenomenon in which water leaks between a discharge pipe 7 of a submersible pump and an elbow pipe 2 and filed an application PCT/KR 03/01282.
An automatic discharge connection device of the submersible pump disclosed in PCT/KR 03/01282 includes, as shown in FIG. 2, a coupling member 10 coupled to the discharge port side of the submersible pump 4 so that the submersible pump 4 is coupled to the elbow pipe 2, and a sealing member 20 for preventing a water leakage by clogging a gap between the elbow pipe 2 and the coupling member 10 when the submersible pump 4 is driven.
The elbow pipe 2 has a flange 2a formed on the inlet side, and a pair of guide bars 3 to which the coupling member 10 is guided stands erect on both sides of the elbow pipe 2.
The submersible pump 4 has a flange 71 formed in the discharge pipe 7, and the coupling member 10 is coupled to the flange 71 by a bolt 72.
Meanwhile, the coupling member 10 includes a ring-shaped portion 11 fixed to the flange 71 of the submersible pump 4, and a sheet portion 12 extending from an upper side of the ring-shaped portion 11 to the guide bars 3. A stepped portion 13 into which the sealing member 20 is inserted is formed in the ring-shaped portion 11. A ring-shaped breakout prevention jaw 14 vertically adjoins the stepped portion 13 and protrudes toward a central portion of the ring-shaped portion 11.
The sealing member 20 is formed in a cylindrical form, and has an inclined front-end portion 21 formed therein such that the front-end portion 21 comes in contact with an inclined face 2b of the flange 2a on the inlet side the elbow pipe 2 with a wide area.
However, when the submersible pump 4 is actuated, reaction force A acts on the submersible pump 4 in an opposite direction to the elbow pipe 2, and pressure B caused by the weight of the submersible pump 4 and water within the water tank act on the submersible pump 4 in a downward direction of the submersible pump 4. The submersible pump 4 and the coupling member 10 are rotated upward in a counter-clockwise direction by means of a resultant force C of the reaction force A and the pressure B, so that a large gap is generated between the lower side of the ring-shaped portion 11 and the lower side of the inlet-side flange 2a of the elbow pipe 2. Accordingly, there was a problem that the sealing member 20 breaks away outwardly from the elbow pipe 2.
Further, the front-end portion 21 of the sealing member 20 of the submersible pump protrudes outwardly from the coupling member 10. Thus, when the submersible pump 4 is coupled to the elbow pipe 2, the front-end portion 21 of the sealing member is caught by the flange 2a of the elbow pipe 2 because the submersible pump 4 falls down. Accordingly, there was a problem that the submersible pump 4 could not be easily coupled to the elbow pipe 2.